The bioconcentration factors (BCFs) of pentachlorophenol (PCP) in different tissues, organs and body fluids of humans were calculated by two methods: 1) from daily intake of PCP and its measured concentrations in different tissues and, 2) from measured half-life and measured PCP concentrations in the human body at steady state using a linear one compartment pharmacokinetic model. The BCFs (based on wet weight) in liver, brain, blood, spleen and adipose tissue of humans as calculated by method 1 were 5.7, 3.3, 1.4, 1.4, and 1.0, respectively. The figures obtained by method 2 were in good agreement to those obtained by method 1.